Thermoelastic Martensite Transformations and the Properties of Ultrafine-Grained Ni54Mn20Fe1Ga25 Alloys Obtained by Melt Quenching

Abstract

Studies of structural and phase transformations in the cast and melt-quenched ferromagnetic four-component alloy Ni₅₄Mn₂₀Fe₁Ga₂₅ were performed using transmission and scanning electron microscopy and X-ray diffraction, The obtained data have been compared with the results of studies of physical characteristics (electrical resistance, thermopower, magnetic susceptibility, magnetization, and temperature coefficients of linear expansion and relative elongation ΔL/L measured by the method of dilatometry) in the temperature range of 2–870 K. This work has established the effects of quenching on the microstructure, magnetic state, critical temperatures, and specific features of thermoelastic martensitic transformations in the alloy.